Infectious Disease Flashcards
Pathogens
• Organism that is capable of causing disease
• Virulence
–High -
–Low -
causes disease in a healthy population
causes disease only in susceptible populations
Opportunistic Infection
(3)
• Non-pathogenic organism
• Low virulence
• Immunocompromised host
Mutualism
(2)
• Interaction between two organisms
• Both organism benefits
Commensalism
(4)
• Interaction between two organisms
• One organism benefits
• Other is neither harmed nor helped
• C. albicans
skipped
Pathogens
ex (10)
• Prions
• Viruses
• Bacteria
• Chlamydia
• Rickettsia
• Mycoplasma
• Fungi
• Protozoa
• Helminths
• Ectoparasites
Viral Infection and Replication
sequence (5)
• Attach
• Penetrate
• Reproduce
• Assemble
• Release
• Transient infections
ex (1)
–Hepatitis A Virus
• Chronic latent infections
ex (1)
–Herpes Simplex Virus
• Chronic productive infections
ex (1)
–Hepatitis B Virus
• Transforming infections
ex (2)
–Epstein Barr Virus, Human Papilloma Virus
Human Herpes Virus (HHV)
(3)
• Humans are the natural
reservoir
• Latency
• Reactivation
HHV-1
Herpes Simplex Virus Type 1
HHV-2
Herpes Simplex Virus Type 2
HHV-3
Varicella Zoster Virus
HHV-4
Epstein Barr Virus
HHV-5
Cytomegalovirus
HHV-8
Kaposi Sarcoma associated virus
Transmission of HSV
(3)
• Contact with affected individual shedding
virus
• Symptomatic active lesions
• Asymptomatic viral shredding
Herpes Simplex Virus Type 1
• Mostly — infections
oral
Herpes Simplex Virus Type 2
• Mostly — infections
genital
Primary Infection With
Herpes Simplex Virus
(3)
• Initial exposure to virus in an individual
without immunity
• Generally occurs at young age after physical
contact with infected individual
• Mostly subclinical disease
–80% of US population has antibodies to HSV
Primary Herpetic Gingivostomatitis
(2)
• Flu-like illness with
fever, malaise,
arthralgia, headache
• Cervical
lymphadenopathy
What Is Recurrent Aphthous
Stomatitis?
(2)
• Focal mucosal
destruction
• T lymphocyte mediated
cytotoxic reaction